Lamp base printing mechanism



NOV. 25, 1952 L TY E 3,619,032

- LAMP BASE, PRINTING MECHANISM Filed Dec. 16, 1950 4 Sheets-Sheet l lnvervto'v: LesLie P. Tater",

b8 r. His A t torneg.

Nov. 25, 1952 L. R. TYLER 2, 1

' I LAMP BASE PRINTING MECHANISM Filed Dec. 16, 1950 4 Sheets-Sheet 2 lrwven' tov: Le'sLie P. T Le T', b5 WC- His A t torney.

Nov. 25, 1952 L, P. TYLER 3 LAMP BASE PRINTING MECHANISM Filed Dec. 16, 1950 I 4 Sheets-Sheet 3 lnvervtovz LesLie P. THLBT,

His A' vtornes.

Nov. 25, 1952 L. P. TYLER LAMP BASE PRINTING MECHANISM 4 Sheets-Sheet 4 Filed Dec. 16, 1950 M 3mm Raw QM m 3% 8% BQ 5% 8w 3w 3w Patented Nov. 25, 1952 UNITED STATES PATENT OFFICE LeslieP. Tyler, Cleveland Heights, Ohio, assignor to General Electric Company, a corporation of New York hpsiicauon December 16, 1-950, Ser'ialNo. 201,087

v 10 Claims. 1

This invention relates generally to, theprint ing of identifying characters on cylindrical objects such as the bases of incandescent lamps. More particularly, it relates to-a mechanism for automatically printing identifying characters on the cylindrical bases of miniature electric lamps and which is adapted to operate in conjunction with rotary turret lam'p finishing machines.

The lamp making machines used in the industry at the present time are generallyof the indexing type wherein manufacturing operations are performed upon the lamps at spaced work stations. The lamps are advanced or indexed from one work station to the next by means of suitable conveyor systems which operate in a series of intermittent or discontinuous steps. For instance, the lamps may be held by the spindles of suitable holders mounted on the periphery of a rotary turret; the manufacturing operation may be performed by mechanical operators disposed around the turret at various stations and adapted to move radially inwards upon the lamps when they are indexed in place. The wide-spread use of machines of this type has made it practically essential that a printing or lamp marking mechanism be capable of operating in conjunction with them in order to be economically feasible.

The marking of electric lamps is generally required in order to permit their identiflcation as to, wattage and ratingand usually as to the maker. in the, case of the larger lamps, for instance, the household type of lamp adapted to operate on the commercial llO-volt circuits, such, markings are relatively easily applied to the curved exterior surface of either the lamp or the base. The marking may be done by means of printing members or templates having a curvature conforming to that of the envelope of the lamp or other portion whereon it is desired to impress the printing. Another device which has been employed is a crescent-shaped printing member which is adapted to swing upon the base of a lamp during the period of time when the lamp is indexed at a predetermined printing station. Although such a method of printing is perfectly satisfactory when the curvature of the surface is moderate or, in other Words, when the printing covers only a fraction of the periphery of a cylindrical base, it is not feasible as a. rule when the printing must cover a major portion of the periphery of the base. Particularly in the case of miniature incandescent lamps wherein the printed characters must cover substantially the whole periphery of the base in order to be eligible, such curved printing members are generally not feasible.

' In the co'pending application of HarryC. fitkins et alqserial No. l95,4 ,'fi ed ov r 3, 1950, entitled Base Printing Apparatus"andassigned to the same assignee as the present invention, there is disclosed and claimed an apparatus for printing identifying characters on miniature incandescent lamps. The apparatus in that application comprises a pair of slidable arms which are adapted to swivel together to grasp a lamp by its base, and to slide one with respect to the other in "order to roll the base. One of the arms carries a printing member which prints the characters on the base during the rolling operation.

The present invention relates to an improved base printing machine of the same generic type as that described in the Atkins et a1. application above, and which is particularly suitable for operation in conjunction with a high speed mini atu're lamp finishing machine.

Accordingly, the principal object or my invention is to provide a new and improved printing mechanism for operating in conjunction with a lamp finishing machine of the rotary turret indexing type for applying identifying characters of'substanti'alsize around the periphery of miniature electric lamp bases.

In accordance with the invention, the characters are printed on the base of the lamp by rolling it against a flat stamp suitably inked for the purpose. The stam is mounted next to e of a pair of serrated gripping plates which are held on radial fingers fastened tea pair of slide rods. The gripping of the lamp is achieved by means of a slight inward rotation at the rods along their longitudinal axes, one with respect to the other, and the rolling "of the lamp between the serrated gripping plates is achieved by causing one of the rods to slide backwards as the other slides forward, both at equal rates with respect to the spindle of the lamp finishing machine which holds the lamp.

For further objects and advantages and for a better understanding of the invention, attention is now directed tothe fol-lowingdescription and accompanying drawings. The features of the invention believed to be novel will be more par ticularly pointed out in the appended claims.

In the drawings:

Fies lc. b and c are simplified fragmentary views of the main elements of the printing mecha nism, 'showing'in pictorial form the sequmeor Operations in printing a lamp base.

Fig. 2 is a plan view, partly in section, of a base printing mechanism embodying the invention and shown in conjunction with a fragment of a lamp finishing machine,

Fig. 3 is a side elevation view of the printing mechanism shown in conjunction with a single lamp base holder.

Fig. 4' is an enlarged side elevation view of a miniature incandescent lamp showing the type of marking or characters which it is desired to imprint on the base of the lamp.

Fig. 5 is a sectional elevation of a portion of the base printing mechanism seen along the section line VV in Fig. 2.

Fig. 6 is a plan sectional view showing a fragment of the printing machine including a pair of control rollers forming part of an interlock mechanism.

Fig. 7 is a plan sectional view through the section line VII-VII in Fig. 5, showing the serrated gripping jaws and the printing stamp of the machine positioned for marking a lamp base.

Fig. 8 is a timing diagram showing the sequences of operations in the mechanism during a printing cycle.

Referring to Fig. 4, there is shown a miniature incandescent electric lamp I of a type which is produced in large quantities by the lamp making industry, generally for use in flashlights. The major. component parts of the lamp are the base 2 which, in this case, is of the miniature screw type, and the glass bulb 3' containing the filament. In general, the manufacturing operation of the lamp finishing machine to which referen'ce is made in the present application comprises joining the bulb to the base, heating the base in order to set the cement contained therein, andsoldering the lead-in wires, one to the end contact '4, and the other to the base shell. The purpose of the printing mechanism of the present'invention' is to print identifying characters such as the markings B014 USA on the base of the lamp, as shown at 5 in the drawing. Although the identifying characters shown in the drawing cover only a fraction of the periphery of the base, in practice the name or trade-mark of the manufacturer of the lamp would also be printed'so that the characters would cover substantially the whole periphery of the base.

- Referring to Fig. 1, the essential functional elements of the printing mechanism for operating on the base 2 of lamp I comprise the printingstamp 6, the cooperating serrated gripping plates or jaws 1 and 8, and the slide rods l0 and H to which the jaws are attached by the radial spring fingers l2 and IS. The different views a; b, and 0 illustrate the sequence of operation of the mechanism in printing the identifying characters on the base 2. It will be understood that the lamp is held in the position shown by means of a suitable holder but is free to spin on its vertical axis.

In Fig. 1a, the slide rods are shown in their retracted position and rotated about their longitudinal axes in such fashion that the jaws are spread apart. From the position shown in Fig. 1a, the slide rods advance towards the lamp to assume the position shown in Fig. 1b. The rods then rotate about their longitudinal axes in opposite directions one with respect to the other so as to force the gripping jaws inwardly together in order to grasp the lamp. In Fig. 1c, the lamp is caused to rotate or spin in its holder by reason of the equal rectilinear movement of the slide rods in opposite directions. Thus slide rod ll continues to move forward whereas slide rod l0 moves backward an equal amount and at the same rate. During the spinning operation, the stamp 6 carried under the gripping jaw 1 bears against the base of the lamp so that the characters are printed on it. The next operation of the slide rods evidently must be to rotate about their longitudinal axes so as to open the gripping jaws and release the lamp, whereupon both slide rods will be retracted to the position shown in Fig. la.

The base printing mechanism, which will now be described in detail by reference to the remaining figures of the drawings, is designated to effect the above-described sequence of operations on a lamp held in a holder of a lamp finishin machine of conventional design. Evidently the sequence of printing operations must be correlated to the indexing cycle of the finishing machine in order for the mechanism to operate successfully. It is necessary to provide for inking the printing stamp during some portion of the cycle of the mechanism. Since it is possible for a lamp holder which does not contain a lamp t be indexed to the printing station, suitable provision must also be made to safeguard the operation of the printing mechanism in such a contingency. The safeguards are provided by means of an interlock mechanism which prevents the inking of the stamp when no lamp is present in the holder.

In order to simplify the description of the mechanism which will now follow, and to facilitate an understanding of its operation, the mechanism will be considered under the following headings:

1. Slide Rod Mechanism 2. Inking Mechanism 3. Interlock Controls 4. Timing Diagram Slide rod mechanism Referring to Fig. 2, the lamps are held in holders [6 which are fastened radially on the periphery of a wheel or turret IT rotatably supported at its center on a shaft I8. The finishing machine is provided with a suitable power drive for intermittently rotating the turret I1 in a counterclockwise direction, as indicated by the curved arrow l9, through a continuous series of small angular increments. These angular increments are such that the base holders advance through one position for each indexing operation of the turret. Thus at the next indexing operation, lamp holder I6" will move to the position occupied by lamp holder 15 in the drawing, whereas lamp holder IE will move to the position presently occupied by lamp holder [6.

The details of the lamp holder it may be seen in Fig. 3. It comprises a bracket 2! which is fastened to the turret II and supports at its upper end a lamp base receiving plate 22 shaped to conform to the outer end of the base 2 of the lamp I. The lamp is held in the plate 22 by means of a spindle .23 provided with a suitable fixture 24 adapted to bear against the bulb 3 of the lamp. A helical spring 25 pushes the spindle 23 and the fixture 24 up against the lamp, thereby to hold it securely in place against plate 22. The lamp may be released by pressing down on the bracket 26 in order to compress the spring 25 and drop the spindle 23.

Referring to Fig. 2, the slide rods [0 and I! along with the associated'parts constituting the printing mechanism are located, with respect to the turret 1?, to operate upon the lamp presently held at the printing station, that is, the

aura-cs2 supports the printing='s'tamp will henceforth he referred "to as the right-hand slide rod, and the other as the left-handsliderod.

The reciprocating movement of the slide rods in their guide bearings is "achieved by means of spring loaded *cam actuated levers. In the ease o'f s'lide-rod -l-ll,-thecomponent elements may:readily be seen in Fig. 3. They comprise a connecting lever 2 1 which is hinged at .28 and carries, at its lower end :a roller 29 riding in a vertical slot in the rod ll], and at an intermediate point, archer-"31 which rides "on a cam disc 32 fastened to a shaft 33. Shaft 33 is driven by means of a "roller chain and sprocket, shown generally at 34, which links it by means of a worm and pinion shown generally at '35, to the cam shaft 36 of the lamp finishing machine. It will be understood that the cam shaft 36 is driven at 'a constant angular velocity by the power drive "of the lamp finishing machine, and not in a series of intermittent steps.

The slide rod l-U moves in an annular guide bearing block 3! which is fastened to a vertical frame plate 3 8 supported by suitable brackets at "M and 42.. The retreat or backward movement of the slide rod away from the lamp holder is brought about by the positive action of the cam disc '32 against'th roller 31 on the connecting lever 21. The advance 'or forward movement of the slide rodjtowards the lamp holder is caused by the action of the coil spring '43 when the cam disc 32 allows it. The knurled thumb screw M permits a slight moveirl'ent of the pivot 28 to the left or right in order to allow a fine adjust ment of the limits of movement oi'the slide rod I'll.

The slide rod H has 'a mechanical linkage similar to that of the slide rod iii, comprising a cam disc 45 "which may he seen in dotted outline in Fig. 3, and a connecting lever '45 which may 'be seen in cross section in Fig.v 2. The cam disc '45 is also fixed to the shaft 33 and drives the slide rod 11 through a linkage with lever and associated elements similar to those that have been described with reference to slide rod 1-0.

As previously mentioned with reference to Figs. la, b, and c, it is necessary to periodically rotate the slide rods [=0 and II about their longitudinal axes with respect to their guide bearings 6 apart, by the positive action of the discrcam 55. whereas. they 'are brought together by the reverse action of. the spring 51.. This prevents damage to the jaws. in case they should encounter an ob struction in attempting to close upon a iamp;

hiking mechanism It is necessary to provide so'memeans for ink-- ing the stamp -6 in the intervals between prim ing operations on -a lamp. in accordance with the invention, this is achieved by causing the jaws to close together at or near to the limit of rearward travel of the slide rods. Referring to Fig. 3, it will be observed that the printing stamp 6 is located beneath the right-hand gripping jaw I and is fastened to the slide rod IO by means of a spring blade 58. The mounting screws 59 at the lower end of the spring blade 58, in conjunction with the horizontal slot in the printing stamp 6, permit adjustment of the position of the stamp. When the jaws close t'o gether in the position shown, the printing stamp contacts the disc platen '6! and picks up for the next printing operation. Referring to Fig. 5, the position of the printing "stamp in picking up ink from the disc platen 6 lisreadily seen. The platen 6| is mounted on a short spindle 62 which carries at its opposite end a sprocket wheel 63. The ink is supplied to the platen by a vertical roller 64 which receives it from a horizontal roller 65, which in turn re-- in order to bring the serrated gripping jaws 1 and 8 together. This is achieved by a slide and roller mechanism in the following manner: The slide rods l0 and II are free to rotate in their guide bearings 31 except inasmuch as they are restrained by the transverse pins 4! and '48 supporting rollers 49 and '50, respectively. These rollers, as may be seen in Fig. 3', ride in horizontal slots 5! and 52 in a slide or cross-head 53 which is fastened to a vertical spindle 54. This spindle carries at its upper end a roller which bears against the intermediate cam disc 55, fastened like the others to the transverse shaft 33 and driven by the roller chain and sprocket linkage 34. The spindle 54 is normally urged upward by the coil spring 51 which causes the roller. 55 to bear against the cam disc 56. The slide rods rotate in such fashion that the gripping jaws are forced apart by a downward movement of the cross head. Since the gripping jaws are mounted at the ends of the relatively long spring fingers i2 and IS, a very slight movement of the cross-head is amplified to produce a considerable movement of the gripping jaws. It will be observed thatth jaws are'forced ce'ives its inkfrom a V-shaped inking reservoir 66 of conventional design.

'Ihevertical roller 64 is adapted to rotate on a shaft which is supported by the bracket 61 extending downwardly from the slide rod I0.

During a reciprocation of the slide rod I'll, the:

vertical roller 64 rolls over the platen '61 and spreads the ink, which it has picked up from the horizontal roller 65, over the surface of the platen. Therearward movement of the slide rod I'll causes the roller 68 afiixed to the bracket 61 to contact the bell crank 69. By means of a suitable spring and pawl arrangement which may be seen in part at H, the rocking of they bell crank 69 indexes the horizontal roller through a predetermined angle so that it continuously picks up ink from the reservoir 56. The shaft on which the horizontal roller 65 and the bell crank 69 are mounted, also carries at its remote end a sprocket which is linked by "a roller chain to the sprocket 63 shown in Fig; '5

As a result, the indexing of the horizontal roller 65 also causes the disc platen B1 to be indexed through a small angle, thereby causing it to revolveintermittently. The revolving of the disc platen 6| along with the to and fro movement of the vertical roller 64 helps in spreading the ink evenly as a thin film on the disc platen.

The quantity of ink picked up by the vertical roller 64 can be varied by adjusting the pressure under which it contacts the horizontal roller 65. This adjustment is effected by turning the knurled thumb screw 44 to shift the pivot point 28'. The vertical roller 64 is made of some nexible material such as rubber and picks up a greater'or lesser quantity of ink, depending upon the extent to which it is deformed against the horizontal roller 65.

Interlock controls stamp which would occur when empty base hold ers are indexed into the printing station. It

will be understood that it quite often happens that the personnel attending the lamp'finishing machine may fail to fill all the lamp holders in any one revolution. Accordingly if the printing stamp were allowed to pick up the same amount of ink irrespectively of whether or not lamp bases are being printed, the ink would accumulate on the stamp. Then, when eventually a holder containing a lamp did become indexed at the printing station, the characters printed on that particular lamp would be blurred due to the runningover of the excess of ink. The mechanism counters such a possibility by means of a mechanical interlock which prevents the printing stamp from picking up ink whenever an empty lamp holder is indexed into the printing sta tion.

The principal elements of the interlock mechanism may be seen in Fig. 6 which is a plan view of that portion of the machine next to the lamp holder on a level slightly vertically above the turret I1, and corresponding approximately to the top surface of the stud 26 projecting horizontally from the spindle of the lamp holder. The principal elements of the interlock mechanism are the lever 13 which is pivoted at 14 with respect tothe vertical frame 38 of the printing mechanism, and which is normally forced in a counterclockwise direction by the coil spring 15. The lever 13 carries at its end nearest the lamp spindle a large roller 15 and a smaller roller 11. At its end remote from the lamp holder, the lever 13 carries a vertical screw 18 whose head is adapted to engage a transverse pin 19 on the vertical spindle 54 which supports the cross-head 53. It will be recalled that the up and down movement of the cross-head 53 controls the axial rotation of the slide rods whereby the gripping jaws are brought together or forced apart. Since the upward movement of the cross-head which causes the jaws to close is brought about by the action of the coil spring 51, it is possible to prevent the jaws from closing by restraining the upward movement of the rod 54. The restraining of the rod 54 is achieved by the head of the screw 18 which may engage the transverse pin 19 on the spindle.

The operation of the interlock is correlated to the presence or absence of a lamp within a holder by the fact that the presence of a lamp results in the spindle 23 of the holder being depressed slightly lower than when a lamp is absent. The roller 16 is so positioned that if a lamp is present within the holder, the stud 8| on the spindle of the lamp holder contacts it and causes the lever 13 to pivot, whereby the screw 18 moves back from the transverse pin 19 and releases the vertical spindle 54 carrying the cross-head. On the other hand, if the lamp holder is empty, the stud 8| rides slightly higher and fails to engage the large roller 16 so that the lever 13 does not pivot and the spindle and cross-head cannot move up.

The large roller 82 seen in Fig. 3 is adapted to engage the transverse bracket 26 and to force it down, whereby to lower the spindle 23 and release the pressure on the lamp l. The purpose of releasing the pressure on the lamp is in order that the jaws may spin the lamp during the printing operation without being required to exert an excessive force on the lamp base. The lamp may be held in place meanwhile by a suitably directed air jet, not shown in the drawing. The lowering of the spindle caused by the roller 82 permits the stud 8| to engage the smaller roller 11 when the base holder has advanced to the printing station.

Timing diagram The sequence of operation of the different parts of the printing mechanism may be understood most readily by referring to Fig. 8 containing the timing diagram. The printing mechanism angle refers to the angular position of the shaft 33 supporting the cam disc. The zero angle corresponds to the state of the printing mechanism as illustrated in Fig. 3, in connection with which the corresponding position of the jaws may be seen most clearly in Fig. la. The indexing of the lamp holders carried on the turret of the finishing machine begins at the 325 angle of the printing mechanism on the preceding cycle, and ends at the 85 angle of the current cycle.

During the interval from 20 to 120 the righthand slide l0 carrying the printing stamp advances the full extent of its movement, which, in the case of an actual construction, was 2%". Beginning at the angle, the left-hand slide rod I l moves forward and will have advance 1%" at the 120 angle. The position of the slide rods then is as illustrated in Fig. 12). It will be observed that the right-hand slide rod has its gripping jaw 1 advanced further than the jaw 8 of the left-hand slide rod. This is to permit the jaws to move in opposite directions during the next portion of the cycle in order to spin the lamp without moving it out of its holder.

During the interval from 0 to 20, provided a lamp is present in the holder to operate the interlock by deflecting the larger control roller 16, the slide rods rotate in order to allow the stamp to pick up ink from the platen 6|. If the base holder is empty, the large control roller is not deflected and the interlock mechanism prevents the jaws from operating and the stamp from picking up ink. At the position, the small control roller 11 is deflected by the projecting stud on the lamp spindle and the interlock mechanism is released whether or not a lamp is present in the holder.

During the interval from to the slide rods are stationary as far as longitudinal movement is concerned, but rotate inwards thereby bringing the jaws together to grip the lamp as indicated in Fig. 1b. During the interval from 130 to 250, the right-hand slide rod [0 moves back whereas the left-hand slide rod 1 l moves forward an equal extent and at the same rate. During this interval, the jaws remain closed and grip the lamp base. It will be recalled that the base is held relatively loosely in its holder at this time by reason of the fact that the lamp holder spindle has been pushed down by the roller 82. The rolling of the base against the jaw 1 causes the characters of the stamp to be imprinted on its peripheral surface.

During the interval from 250 to 260, the slide rods rotate longitudinally so as to open the jaws and the printed lamp is released in the lamp holder. From the 270 to the 360 positions, both the right-and left-hand slides retreat and return to the rest position corresponding to the 0 angle.

Although the base printing machine illustrated in the drawings has been described in detail as to its component parts, it will be understood that such detail is for the purpose of explanation and not in order to restrict the invention thereto. It is possible to make many variations as to the details of the mechanism in order to adapt it to op- 9 crate in conjunction with different lamp-making. machinery. Moreover, the mechanism canbeerrlarged or modified to print: characters on. differ.- ent sizes and types. of lamps or: other similar cylindrical devices. The appended claims. are therefore intended to cover any such modificae 'tions coming within the. true-spirit and scope: of

theinvention.

What I claim as new. and: desire to secure by Letters Patent of the United Statesis:

I. A mechanism for marking characters onthe cylindrical portions of devices periodically presented. at a work station, comprising a pair of slide rods in substantially parallel alignment, means mountingsaid slide rodsformovement forward towardsaid device at saidstation, a pair'of gripping jaws mounted in radially-displaced alignment at the forward ends of said slide rods, a marking stamp carried on one of said slide rods proximate to one of'said' jaws, means for rotatingsaid slide rodsabout their'longitudinal axes inorder toforcesaid jaws together and gripsaid device, and means for moving one of said slide rods with respect to the other'inorder tospin said device between said-jaws, thereby to cause the periphery of said device'to roll against said stamp.

2; A mechanism for marking characters on'the periphery of the cylindrical portions of devices periodically presented at a work station, comprising a pair of slide rods in substantially parallel alignment, means mounting said slide rods for'movementforward' towards said device at said station, apair of gripping jaws mounted in radially displaced alignment at the" forward ends of 'saidsliderods, amarking stamp carried on one of said slide rods proximate to one of. said jaws, means for rotating said slide. rods about their longitudinalaxes in order. to force, saidv jaws to.- gether and-grip said. device. and means for advancing one of said slide rods and simultaneously withdrawing the other in order to spin said device between said jaws While fixed in position at said station, thereby to cause the periphery of said device to roll against said stamp;

3. A mechanism for marking characters on the periphery of the cylindrical portions of devices periodically presented in fixed alignment at a work station, comprisin a pair of slide rods mounted in substantially parallel alignment and adapted. to move forward towards said device at said station, a pair of 'grippinggjaws mounted on radial fingers at the forward; ends of said slide rods and in parallel facing alignment one with respect to the other, a marking stamp carried on one of said slide rods proximate to one of said jaws, means for moving said slide rods forward in order to cause said jaws to encompass said device, a linkage actuated by said means for rotating said slide rods about their longitudinal axes in order to force said jaws together and grip said device, said means being further adapted to advance one of said slide rods and simultaneously withdraw the other in order to spin said device between said jaws while fixed in position at said station, thereby to cause the periphery of said device to roll against said stamp.

4. A mechanism for printing characters on the periphery of the cylindrical bases of electric lamps periodically presented in fixed alignment at a work station, comp-rising a pair of slide rods mounted in parallel alignment and adapted to slide forward towards said lamp at said station, a pair of gripping jaws held by radial fingers secured. tousaidisliderods at. their; forward ends, said gripping;jawsbeingstraight and extendedin substantial parallelism to said slide rods, means for causing said: slide rods to advance towards said. lamp: and; said jaws to: encompass it on opposite:sides,.meanswfor rotating saidsliderods about their longitudinal; axeszin. order to force said laws together whereby to grips'aidlamp therebetween, a printing. stamp: carried at the. forward end. of one of saidzrods in substantialparallel.alignment to the gripping law associated.therewith,lsaidfirst named meansbein further adaptedto. cause one of said rods to slide with respect to. the other while said jaws are. closed, thereby to. roll. said lamp against said stam'pand imprint the characters of said stamp on the peripheral surface of said base.

5. A mechanism for printing characterson the periphery ofthe cylindrical bases of electric lamps periodically presented in fixed alignment at a work station, comprising a pair of slide. rods mounted in parallel alignment and adapted to slid'e'forward towards said lamp at said station, a-. pair of gripping jawsheld by radial fingers-secured to said slide rods at their forward ends, said gripping jaws being straight and extended in substantialparallelism to said slide rods while facing each other; means for causing said-slide rods to-advance towards said lamp and said jaws to encompassit' on-opposite sides, means for rotating said slide; rods about their longitudinal axes while so advanced in order'to force saidjaws together-whereby to rip said lamp therebetween, a printing stamp carried at the forward end of one ofsaid'rods insubstantial parallel alignment to the gripping J'aw associated therewith, saidfirst named. means being further adapted to advance one of'said slide rods and simultaneously withdraw the other-at the same rate in order to cause said lamp to spin between said. jaws whileclosed and" without moving said lamprout' of its station, thereby toimprint. the characters of said stam on the peripheral surface ofsaid base.

6., Azmechanismfor printing characters on the periphery of the; cylindrical bases of electric lamps periodically presented at a work station, comprisingia' pair of rods supported in substantially parallel alignment in guide bearings and adapted to" slide along, and rotate about their longitudinalaxes. with respect to said bearings, gripping jaws mounted on radial fingers. fase ten'edto said rods at their forward ends; and extending in'facing alignmentparallel'to theaxes of said slide rods, a printing stamp carried'on one of said slide rods in proximity to its associated gripping jaw, cam actuated linkages for causing said slide rods to move forward and rotate whereby to cause said gripping jaws to encompass said lamp and grip it on opposite sides, said linkages being further adapted to advance one of said slide rods while withdrawing the other whereby to spin said lamp between said jaws without moving it out of said work station, said spinning being adapted to roll the base of said lamp against said stamp for printing characters thereon.

'7. A mechanism for printing characters on the periphery of the cylindrical bases of electric Iampsperiodically presented at a work station, comprising a pair of rods supported in substantially parallel alignment in guide bearings and adapted to slide along and rotate about their longitudinal axes with respect to said bearings, gripping jaws mounted on radial fingers fastened to said rods at their forward ends and extending in mutually facing alignment parallel to the axes of said slide rods, a printing stamp carried on one of said slide rods in proximity to its associated gripping jaw, cam actuated linkages for causing said slide rods to move forward and rotate whereby to cause said gripping jaws to encompass said lamp and grip it on opposite sides, said linkages being further adapted to advance one of said slide rods while withdrawing the other whereby to spin said lamp between said jaws without moving it out of said work station, said spinning being adapted to roll the base of said lamp against said stamp for printing characters thereon, and means for automatically inking said stamp in between printing operations, said means comprising an inking platen located for contacting said stamp during an intermediate rotation of said slide rods.

8. An electric lamp base printing mechanism adapted to operate upon a lamp at a station of a lamp-making machine of the indexing turret type comprising a pair of slide rods mounted in substantially parallel alignment and adapted to move forward towards a station of said machine, a pair of gripping jaws mounted in facing relationship on said slide rods and supported at a substantial radial distance from their axes, a printing stamp carried on one of said rods close to one of said jaws, cam actuated lever linkages for advancing said rods towards said station in order to cause said jaws to encompass said lamp, a cam actuated slide and roller mechanism for rotating said rods about their longitudinal axes in a manner to force said jaws together whereby to grip said lamp therebetween, said lever linkages being further adapted to advance one of said rods with respect to the other in a subsequent operation whereby to spin said lamp between said jaws in order to roll it against said stamp and imprint the characters of said stamp on its base.

9. An electric lamp base printing mechanism adapted to operate upon a lamp at a station ofa lamp making machine of the indexing turret type comprising a pair of slide rods supported by guide bearings in substantially parallel alignment and adapted to move forward towards a station of said machine, a pair of gripping jaws mounted in facing relationship on said slide rods and supported at a substantial radial distance from their axes, a printing stamp carried on one of said rods close to one of said jaws and extending parallel to it, a cam actuated lever linkage for advancing said rods towards said station in order to cause said jaws to encompass said lamp,

12 a cam actuated slide and roller mechanism for rotating said rods about their longitudinal axes in a manner to force said jaws together whereby to grip said lamp therebetween, said lever linkages being further adaptedto advance one of said rods and withdraw the other at an equal rate in a subsequent operation whereby to spin said lamp between said jaws in order to roll it against said stamp and imprint the characters of said stamp on its base.

10. An electric lamp base printing mechanism adapted to operate upon a lamp at a station of a lamp making machine of the indexing turret type comprising a pair of slide rods supported by guide bearings in substantially parallel align-- ment and adapted to slide along and rotate about their longitudinal axes with respect to said bearings, a pair of gripping jaws mounted on radial fingers fastened to said rods at their forward ends and extending in mutually facing alignment parallel to said axes, a printing stamp carried on one of said rods is proximity to its associated gripping jaw and extending parallel to it, a cam actuated lever linkage for advancing said rods towards said station in order to cause said jaws to encompass said lamp, a cam actuated slide and roller mechanism for rotating said rods about their longitudinal axes in a manner to force said jaws together whereby to grip said lamp therebetween, said lever linkages being further adapted to advance one of said rods and withdraw the other at an equal rate in a subsequent operation whereby to spin said lamp between said jaws in order to roll it against said stamp and imprint the characters of said stamp-on its base, and means for automatically inking said stamp comprising an inking platen located for contacting said stamp during an intermediate operation of said slide and roller mechanism adapted to pivot said stamp against said platen.

LESLIE P. TYLER.

REFERENCES CITED The following references are of record in the 

